Tolterodine and Clarithromycin Interaction
Drug interaction information between Tolterodine and Clarithromycin.
Tolterodine and Clarithromycin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Tolterodine and Clarithromycin. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Clarithromycin stops the body from breaking down tolterodine, leading to higher levels of the drug in your system. This is more likely to happen if your body already processes certain medicines slowly.
FDA Label Information
Lurasidone: [See Contraindications ( 4.7 )] Antispasmodics: Tolterodine (patients deficient in CYP2D6 activity) Use With Caution Tolterodine: The primary route of metabolism for tolterodine is via CYP2D6. In this population subset, inhibition of CYP3A results in significantly higher serum concentrations of tolterodine. Tolterodine 1 mg twice daily is recommended in patients deficient in CYP2D6 activity (poor metabolizers) when co-administered with clarithromycin.
Tolterodine Also Interacts With
- Omeprazole minor
- Hydrochlorothiazide minor
- Fluoxetine minor
- Furosemide minor
- Estradiol minor
Clarithromycin Also Interacts With
- Quetiapine major
- Pioglitazone major
- Fluconazole major
- Cyclosporine major
- Lurasidone major
Frequently Asked Questions
What SPL severity band is on file for Tolterodine + Clarithromycin?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Clarithromycin has 81 labeled pairs on file vs Tolterodine's 15. In the moderate band specifically: Tolterodine has 1; Clarithromycin has 35 (also Omeprazole, Methylprednisolone, Sildenafil, Valproate).
What mechanism field is on file for Tolterodine and Clarithromycin?
Clarithromycin stops the body from breaking down tolterodine, leading to higher levels of the drug in your system. This is more likely to happen if your body already processes certain medicines slowly.
Clarithromycin carries more major-labeled pairs than Tolterodine
SPL source-record counts only. This page's band is moderate · classes on file: Tolterodine (Anticholinergic (Overactive Bladder)); Clarithromycin (Macrolide Antibiotic).
Clarithromycin has 16 major-labeled pairs vs Tolterodine's 0. This page itself is in the moderate band, not the major band.
0 major · 1 moderate · 14 minor · 15 total
Tolterodine has no other moderate-band peer in this dataset besides Clarithromycin.
16 major · 35 moderate · 30 minor · 81 total
- Other moderate peers for Clarithromycin
- Omeprazole
- Methylprednisolone
- Sildenafil
- Valproate
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.